https://en.bitcoin.it/wiki/Mining_hardware_comparison
https://www.ledgerwallet.com/products/3-ledger-hw-1
https://www.cryptocompare.com/mining/bitmain/antminer-u3/
https://shop.bitmain.com/productDetail.htm?pid=00020160307072415240XwaQIqfF06D3
https://www.bitcoinmining.com/usb-bitcoin-miner-setup-guide/
